His Pools series features public pools from Germany, Iceland and Italy all photographed from directly overhead and set against an artistic pattern.

Initially when he started back in 2000 he chartered helicopters to capture the pools, but now uses the less expensive drone technology, via a multicopter with a gimbal and camera attached.

Zirwes acquires permission beforehand, and in post-production adds the tiles that surround each pool to create a tessellating pattern. This provides a uniform backdrop that brings the shapes and colours of the pools into sharp relief.